Introduction: AC and DC Voltage Relegated Power Supply
I have finally completed my AC and DC Relegated Power Supply after months of procrastinating and i have to say that i am pretty happy with the result .The modeler design features the classical LTC3780 module and a 4000W AC regulator.It also has two Peacefair LCD power displays that displays Voltage,Amperage, Wattage and Watt hours for both AC and DC modals. All that you have to do is to watch the videos to witness it's construction overview, tips and tricks.
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Step 1: First Here Is Some the Parts That You May Need
Here is a list of links to all of the major parts
You may need to have some other parts that you can scavenge
like a 80mm fan, banana plug connectors, a bus bar, nobs, switches and lots of high amp wire, for that you can just cut open an old mains cable.
Step 2: All the Tools (basically Everything Except the Garden Hose)
As for the tools you may have to go to the shed to pick up some power tools like a grinder and drill, if you have a metal case, but you can get away with a dermal if it is a plastic case. But for the most part you will only have to use some common tools like pliers, screwdrivers and wire cutters. The only special things you may need is a soldering iron and electrical solder wire (the thin stuff is the good stuff) some thermal paste or epoxy and a multi meter but if you are reading this you may probably already have these.
Step 3: Initial Testing (or You Are Going to Have a Bad Time)
Make sure you test everything before you put them in, from switches to diodes to wires, this is where the multi meter will come is useful. Also add thermal grease between the heat sinks and the transistors of the 24v switching power supply and the AC Regulator because the amount and quality of the thermal grease the manufactures apply is usually abysmal. You can also use epoxy instead if you do not intend to replace the transistors, just make sure it’s pressed on good.
Step 4: Case, Box ... Whatever
I have a metal case of 13cm High, 20cm Wide and 18cm long,that I have scavenged. But any case will do just as long as all of your components will fit inside. Do a test fit of all of the components and if you are satisfied everything will fit, drill some holes and screw the modules in place, I used 4mm screws and nuts to bolt them in place. You can also stick non slip pads to the bottom of the box to help prevent it from scooting around your table.
Step 5: Wiring the Main Modules
Wiring the modules together is as easy as 3.14159. So I have included a pictograph instead of a circuit diagram. Just make sure to read the markings on the modules and double check connections before you power up. I have added a 500k and 200k potentiometers to the LTC3780 module to make it easy to adjust the voltage and current from the front panel. An alternate configuration for the DC side would be to replace the 24v switching power supply, the 3.3v&5v regulator module and the 12v regulator module with a Computer's ATX power supply. It just depends on the amount of space/capital you have available.
Step 6: Wiring the Front Panel LCD's (the Hardest Part)
The front panel LCD's is a bit tricky. They only switch on if they are supplied a specific minimum amount of voltage flowing, as I explained in the first video. But using the 3.3v/5v regulator you can overcome this buy wiring up the required voltage (use a multi meter to test this) to the input or the output of the LCD's on-board voltage regulator. On the back of the LCD's cover you will find a circuit diagram displaying how to wire the LCD's up to give readings.
Step 7: Safety Last?
Whenever you create a circuit make sure that you put in a switch as close to the main power source as you can, I have a switch at the mains and two more before the AC regulator and the LTC3780. Additionally when you add in the switches make sure that they are rated higher for the voltage and current that you are going to be using in it, I am using 250v 24A switches. The outputs must have a fuse to protect the circuitry behind it. The input (from the wall) must also have a fuse as well to protect your house. A special note for any AC circuit you make is be sure to put the switch on the LIVE side or you may get a shock when you think the device is supposed to be off. A special note for this DC circuit is that you may want to add a diode on the positive output to avoid those pesky magical pixies from jumping back into the LTC3780 module during a battery charge and frying it, the diode must have a proper heat sink to dissipate the current that you are going to subject it to. Be sure that there is no way the front panel terminals are going to short out, I used a wooden plank as a front cover to prevent this. Lastly be sure to add ground wires to all the metal cases of the modules and test the continuity for the ground.
Step 8: Final Testing (more Testing, Hooray!!)
In this second video i go over the final testing of the apparatus and some tips and tricks operating it.